A new Covid-19 variant, officially known as NB.1.8.1 and nicknamed Nimbus, is now the most common strain in the US, according to the US Centers for Disease Control and Prevention.
The CDC said it is “aware of increasing detections” of Nimbus in the US, where it monitors spread of the virus through nasal and wastewater samples collected via its airport screening program. Nimbus makes up between 13% and 68% of circulating Covid strains, according to a spokesperson for the Department of Health and Human Services. Estimates from the two-week period ending June 21 show that Nimbus made up 43% of US cases.